Peptidyl leukotrienes signal through at least two cysteinyl leukotriene receptors. The control of expression of these two receptors is not well understood. The current project will propose to study the effect of proinflammatory cytokines on gene and protein expression of both receptors in human cells. Assays of gene expression, steady state mRNA expression, and cellular protein expression have been developed. Human cell lines which express either LTR1 or LTR2 are being studied.